• 한국자동차공학회논문집
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• 제4권3호
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• pp.168-175
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• 1996

Except the collision avoidance performance related to the rapid lane change, the 4WS vehicle has better dynamic stability and handling performance than the conventional 2WS vehicle which has close relation with the driver's safety, a 4WS conrol method with the effect of steering wheel angular velocity is proposed based on the fact that the driver steers abruptly the steering wheel to avoid the collision. And the effects of the proposed 4WS control method are investigated on the dynamic stability and handling performance by using the ISO lane change test code.

• Asian-Australasian Journal of Animal Sciences
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• 제28권5호
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• pp.639-646
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• 2015

The effects of Saccharomyces cerevisiae supplementation ($6.6{\times}10^8cfu$) and anhydrous ammonia treatment (3%) of wheat straw (WS) were investigated on in-situ dry matter (DM) degradability, and on rumen fermentation and growth performance of lambs. Rumen-fistulated Menemen sheep fed a diet with and without live yeast were used to assess the DM degradability characteristics of WS and ammonia-treated wheat straw ($WS_{NH3}$). Twenty-six yearling Menemen male lambs were fed in four groups. Lambs of control group (WS) received untreated WS without supplemental yeast, whereas other three groups were fed WS treated with anhydrous ammonia ($WS_{NH3}$ group), untreated WS and yeast (WS+YEAST group) or WS treated with anhydrous ammonia and yeast ($WS_{NH3}$+YEAST group). Supplemented live yeast (4 g/d) was added in the diet. Lambs were offered untreated or ammonia treated WS ad-libitum and concentrate was fed at 1% of live body weight. The degradability of the water-insoluble (fraction B) was significantly increased by all of the treatment groups. Potential degradability (A+B), effective DM degradability's (pe2, pe5, and pe8) and average daily weight gain increased only in $WS_{NH3}$+YEAST group (p<0.05). Voluntary DM intake was not increased by the treatments (p>0.05), but voluntary metabolizable energy and crude protein intake were increased by $WS_{NH3}$ and by $WS_{NH3}$+YEAST (p<0.05). Average daily rumen pH was not affected by any of the treatments, but average daily $NH_3$-N was significantly higher in the $WS_{NH3}$ and $WS_{NH3}$+YEAST groups, and total volatile fatty acids were significantly higher in the WS+YEAST and $WS_{NH3}$+YEAST groups. In conclusion, the improvement of feed value of WS was better by the combination of ammonia-treatment and yeast supplementation compared to either treatment alone.

• 한국재료학회지
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• 제31권8호
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• pp.458-464
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• 2021

Tungsten disulfide (WS₂), a typical 2D layerd structure, has received much attention as a pseudocapacitive material because of its high theoretical specific capacity and excellent ion diffusion kinetics. However, WS₂ has critical limits such as poor long-term cycling stability owing to its large volume expansion during cycling and low electrical conductivity. Therefore, to increase the high-rate performance and cycling stability for pseudocapacitors, well-dispersed WS₂ nanoparticles embedded in carbon nanofibers (WS₂-CNFs), including mesopores and S-doping, are prepared by hydrothermal synthesis and sulfurizaiton. These unique nanocomposite electrodes exhibit a high specific capacity (159.6 F g^-1 at 10 mV s^-1), excellent high-rate performance (81.3 F g^-1 at 300 mV s^-1), and long-term cycling stability (55.9 % after 1,000 cycles at 100 mV s^-1). The increased specific capacity is attributed to well-dispersed WS₂ nanoparticles embedded in CNFs that the enlarge active area; the increased high-rate performance is contributed by reduced ion diffusion pathway due to mesoporous CNFs and improved electrical conductivity due to S-doped CNFs; the long-term cycling stability is attributed to the CNFs matrix including WS₂ nanoparticles, which effectively prevent large volume expansion.

• 오토저널
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• 제12권3호
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• pp.21-29
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• 1990

Equipments of passenger cars with modern technologies are gaining their importance. Related with such developments, the four-wheel steering system (4WS) was introduced recently to a few passenger cars in the market. The most important research goal on this new steering system is improvement of active safety, in other words, improvement of handling characteristics of vehicle stability and maneuverability. This paper presents a computer-based study about the effects of 4WS system on the vehicle handling characteristics. A simple bicycle model of 2 d.o.f. is used for the development of four wheel control algorithms of 4WS system, and the rear wheel control strategies are applied to a complex vehicle model of 16 d.o.f. for simulation of selected ISO-driving tests. The 4WS systems, which reduce the sideslip angle at the mass center of vehicle to almost zero, show much improved handling characteristics compared to that of the conventional 2WS system. These 4WS systems, however, result in vehicles with eigen-steer characteristics of extreme understeer behaviour.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2017년도 춘계학술대회 논문집
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• pp.167.1-167.1
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• 2017

전이금속 디칼코게나이드는 서로 다른 전이 금속원소와 칼코겐 원소의 결합으로 이루어진 층상 구조의 물질이다. 그 중 텅스텐 이황화물($WS_2$)은 전이금속 화합물로써 풍부한 매장량으로 인하여 가격면에서 매우 저렴하며, 높은 온도에서도 잘 견딜 수 있는 열 내구성이 강해 물 분해 반응에서 촉매로 사용될 수 있는 가능성이 제시되었다. 이러한 $WS_2$을 매장량이 적은 고비용의 백금계 촉매를 대체하기 위한 물질로서 많은 연구가 활발히 진행되고 있다. 본 연구에서는 $WO_3$ 콜로이드 용액을 전기 영동 및 황화 처리 이용하여 $WS_2$를 합성하여 수소 발생 반응(Hydrogen Evolution Reaction, HER)촉매로서의 가능성을 확인하였다.

• Food Science and Biotechnology
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• 제14권1호
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• pp.108-111
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• 2005

To improve water-resistance and physical properties of sodium alginate film, effects of sodium alginate and plasticizer concentrations, divalent cation types and concentrations, and immersion time of films into divalent cation solutions on sodium alginate films were evaluated, based on elongation strength (ES), elongation rate (E), water vapor permeability (WVP), and water solubility (WS). Film made from 1.5% sodium alginate solution (w/w) had low WVP and WS, which are optimal characteristics for application of film preparation. Addition of plasticizer increased E and WS. Less than 2% $CaCl_2$ addition and 15min immersion time reduced WVP, WS, and E significantly (p<0.05). Sodium alginate films treated with $CuCl_2$, and $ZnCl_2$ solutions had lower WVP and WS, whereas $MgCl_2$ had no influence on improving water resistance of films.

• 한국양식학회지
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• 제20권1호
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• pp.56-59
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• 2007

Effect of dietary nutrient composition on growth and body composition of juvenile olive flounder Paralichthys olivaceus with different feeding strategy was determined. Twenty-five fish averaging 16 g were randomly distributed into 12, 180 L flow-through tank each. Four treatments in triplicates were prepared: fish were fed to satiation twice daily by the control diet for 8 weeks as the control group (Con) and fish were fed to satiation twice daily by the control and high nutrient diets for 6 weeks after 2-week fasting (2WS-6WFC, 2WS-6WFHN, respectively) and finally, fish were fed to satiation twice daily by the high nutrient diet for the consecutive 3 days after 4-day fasting for 8 weeks (4DS-3DFHN). No significant difference was found in either survival or weight gain of flounder among treatments. Feed efficiency ratio (FER) for fish in the 2WS-6WFHN treatment was significantly higher than that for fish in the Con and 2WS-6WFC treatments. Protein efficiency ratio (PER) of fish in the 2WS-6WFHN and 4DS-3DFHN treatments was significantly higher than that of fish in the 2WS-6WFC treatment. In conclusion, manipulation of dietary nutrient composition and/or feeding strategy can effectively improve growth of juvenile olive flounder without growth retardation at restricted feeding regime.

• Journal of Genetic Medicine
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• 제7권1호
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• pp.45-52
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• 2010

목 적: 윌리암스증후군 아동의 인지와 관련된 두 가지 특성을 검증하고자 하였다; 윌리암스증후군 아동은 언어성 지능이 동작성 지능 보다 유의하게 높다; 윌리암스증후군 아동은 시공간기능의 선택적 저하를 보인다. 대상 및 방법: 평균연령 $90.86{\pm}20.73$개월의 5명의 윌리암스 증후군 아동의 인지적 특성을 연령 및 성별이 유사한 12명의 프라더윌리증후군 혹은 다운증후군 아동의 인지적 특성과 비교, 분석하였다. 결 과: 윌리암스증후군 아동에서 언어성 지능 항목의 합은 $15.71{\pm}9.27$, 동작성 지능 항목의 합은 $14.29{\pm}7.50$으로, 언어성 지능과 동작성 지능 간의 유의한 차이를 보이지 않았다. 윌리암스증후군, 프라더윌리증후군, 다운증후군 아동들간의 언어성 지능의 유의한 차이는 관찰되지 않았다. 윌리암스증후군 아동에서 시공간지각과 관여된 세부항목의 선택적 저하는 관찰되지 않았으나, 물체조합 항목에서 프라더윌리증후군 아동에 비하여 유의한 기능의 저하를 보였다. 결 론: 윌리암스증후군 아동이 전체 지능에 비하여 상대적으로 높은 언어성 지능을 보인다는 일반적인 개념은 본 연구에서는 관찰되지 않았다. 동시에 윌리암스증후군 아동은 프라더윌리증후군이나 다운증후군 아동과의 비교 시에도 우수한 언어기능을 보이지 않았다. 그러나 윌리암스증후군 아동은 프라더윌리증후군 아동과 비교 시 현저히 낮은 시공간기능을 보였다.

• Journal of information and communication convergence engineering
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• 제7권3호
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• pp.253-257
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• 2009

As the value of B2B integration gets more importance and the business process becomes more complex, BPEL4WS standard has been focused for the solution of the problems which is based on web service technology. Many vendors implement the standard in their systems to integrate B2B and web service based inner-Enterprise Application(EA)s. But there is no way to use the standard to integrate non-web service based EAs, because the standard is designed only for Service Oriented Architecture (SOA) over web services. This paper proposes Hybrid Service Orchestration Framework to participate web services and also non-web service based EAs in the business process as a partner using BPEL4WS standard. The framework introduces Hybrid Service Architecture to represent non-web service based EAs as a service, so BPEL4WS could be used to integrate web services and non-web service based EAs. And the framework also introduces Hybrid Service Toolkit to support software level facilities. The paper also introduces Hybrid Orchestration System that is based on Hybrid Service Orchestration Framework.

• 한국농공학회지
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• 제31권1호
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• pp.45-57
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• 1989

The hydrologic model FESHM was introduced and its applicability was investigated in an attempt to analyze the rainfall-runoff relationships of urban small watersheds and to hereafter predict the envi-ronmental changes. Basic data on rainfall, water level, geomorphological characterisitics and land use were obtained from Yeonwha stream watershed located in Chonju-si Dukjin-dong. WL-5 for simulation o subshed WS# 1(136.7 ha) with urban district and WL-1 for total watershed WS#5 (278.78 ha) we'e selected as gaging points. The main results gained through applications were summarized as follows. 1. Direct runoff ratio caalculated from a simple separation method for WS#5 WS# 1 was 2O~39%, 38~62%, respectively. 2. Simulations for the runoff estimation were carried out for each watershed using 5 rainfall events, the simulation errors had the range of 2~ 30%, O~ 63% and O 120 minutes for the runoff volume, peak flow and peak time, respectively. 3. The effect of landuse change by urbanization was tested to WS# 1, runoff volume before development was estimated as from tenth to twentieth against after development.